MyDigitalLife forum member FaiKee has posted a great thread full of lots of Windows 8.1 information. He detailed some information regarding how the integrated Skydrive will work in Windows 8.1, changes to uninstalling apps, and changes to the Windows Store.

SkyDrive does not automatically sync all your SkyDrive files to the PC. Instead it downloads placeholder files for all of your files on SkyDrive. Placeholder files are shown in the app and in the SkyDrive folder in File Explorer. These small files look like the full file, and have thumbnails and metadata, but they take a tiny fraction of the disk space of the full file. When you open a placeholder, the SkyDrive engine downloads the full file in the background. When you open a file this way, SkyDrive also marks the file as Available offline, so that the files you use will be kept in sync on this PC. Only files marked “Available offline” in details view will be available when your PC is offline.

Note: By default, placeholder files will be downloaded even on metered networks. You can change this in the PC Settings, SkyDrive, Files interface.

If you uninstall an app, you can now choose if it is removed from all PCs or only this PC, as shown below.

The image above shows the new options in the app bar.

Windows StoreThe Windows Store app has been updated in Windows 8.1 Preview. This includes the following changes:

You must sign in to the PC with a Microsoft Account to use the Store. There is not a sign–in option when you open the Store as a local account user.

If you are on a local account, you will be guided to change your Windows sign–in to a connected account.

If you are signed–in with a Microsoft Account, you can still use the Change user option on the account page to view the Store as a different user.

The app bar has more options. See the image above.

Windows Store apps are updated automatically. This does not happen while connected to a metered network.

Apps can do more on Windows 8.1 Preview. This means some apps will be offered only to this version of Windows:

Apps designed for Windows 8 work on Windows 8.1 Preview.

Apps designed specifically for Windows 8.1 Preview will not be offered for installation on Windows 8. These apps work only on Windows 8.1 Preview.